The solenoid is a coil of wire, and the plunger is made of soft iron. The magnetic field is formed around the coil when an electric current passes through it and draws the plunger in. We can say that the solenoid is responsible for converting electrical energy into mechanical work.
More simply, a solenoid converts electrical energy into mechanical work. The coil is made of many turns of tightly wound copper wire. When an electrical current flows through this wire, a strong magnetic field/flux is created.
The solenoid simply works on the principle of “electromagnetism”. When the current flow through the coil magnetic field is generated in it, if you place a metal core inside the coil the magnetic lines of flux is concentrated on the core which increases the induction of the coil as compared to the air core.
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